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-   -   Dedicated Lemons/Chumpcar Thread (https://www.rx7club.com/race-car-tech-103/dedicated-lemons-chumpcar-thread-882322/)

RacerJason 10-12-11 08:11 PM

Hey guys, I've made this thread a Lemons/Chumpcar a co-thread. Let's see how it works out... I'm sure both groups share much in common.

mschiap 10-12-11 08:34 PM

Great! We'll be racing our first-gen in a Chumpcar race at AutoClub Speedway (Fontana) this weekend. Look for the Pink Pig ;)

cheseroo 10-17-11 10:58 PM

Chump/Lemons
 
I guess I should jump in here as well. We ran the Fontana Chump race last weekend and spent a fair bit of time chasing the pink pig around. Cooked off the tires on the first day and switched to much harder M+S tires for the second day (it's all we had). Ended up overheating the rear end and spitting out the oil with 3 hours to go. The oil drips were smoking as they came out of each of the output shaft seals so she got a wee bit warm. I had a spare but I figured that by the time that the thing cooled down enough to get near it the race would have been over so we called it a weekend. Garage stinks of burned oil. I'll get the rear end sorted and probably rebuild the gearbox prior to the Buttonwillow Lemons race in December. Any preferred vendors for synchros?

Rich

Mazdarita #55

mschiap 10-18-11 01:46 PM

What's a syncro? ;) Whenever the transmission gets too beat-up to shift, I just go to the junkyard and get another.

We got lucky this weekend - nothing broke. Felt really good to just do brake pads on Saturday night.

Michael

PS:we run "Red Line 57904 (75W90) Synthetic Gear Oil" in our differential, and it works well for us. It comes with LSD additive already in the fluid.

cheseroo 10-18-11 05:00 PM

Ya well, this one is a JY trans that I just put in and 3rd gear probably has another race day or so left in it. The one it replaced you had to wait an awful long time to get 3rd so that's the one I'm thinking of rebuilding. I haven't priced out a seal kit or synchros (i figger to replace 2nd & 3rd) and that will determine whether it's worth rebuilding or getting another S5 NA trans that got pitched in a T2 swap. As far as gear oil I was running Lucas 75/90 with the built in LSD stuff. It was free but I think I'll try Red Line this time around as I've had good luck with it.

mschiap 10-19-11 09:03 AM

2 Attachment(s)
here are some pics of your car in action

cheseroo 10-19-11 10:52 AM

Fontana
 
Looks like you managed to capture the one time we passed you :lol:

bob13bt 11-28-11 10:13 PM

Are elaborate costumes and bodywork required? Or can I just race a plain ol $500 car?

mschiap 11-29-11 06:05 AM


Originally Posted by bob13bt (Post 10879860)
Are elaborate costumes and bodywork required? Or can I just race a plain ol $500 car?

For Chumpcar, no goofy theme, costumes, or bodywork required. Just show-up with a $500 car. Read the rules carefully, though - you will need to substantiate the value of your car with 10 examples (Craigslist ads) of similar cars from different geographic regions.

cheseroo 11-29-11 11:20 AM

Lemons/Chump
 

Originally Posted by bob13bt (Post 10879860)
Are elaborate costumes and bodywork required? Or can I just race a plain ol $500 car?

I've only done 1 Chump race and they didn't care less about the costumes/bodywork which is kind of disappointing if you already have it. The tech people didn't say a word about it but a LOT of other people got a kick out of the sombrero and being able to fetch margaritas out of the blender on the back deck. No need to bring bribes to Chump whereas it's part of the custom at Lemons (one of the other teams is giving them a pool table this weekend). I typically give them cigars and a bottle of good tequila.

In Chump, they want to see 10 internet ads for running/driving examples of similar cars. Wrecked or barely running seems to be ok. If you have a Gen 2 car, Gen 1 ads won't work.

For Lemons, they will want to see what you paid for the car. If you paid $1500, you need to sell $1000 worth of parts off your car to make it $500. Keep receipts. If you sell parts, keep copies of the ads, take a picture of you handing the part over to the buyer and the buyer handing you money. Documentation is key with either series. If you are like us and have a fairly new car (S5), a fancy theme buys you some slack. And yes, they can tell the difference between an S4 & S5. It took them about 2 seconds to look at the VIN and say "Oh!, it's an S5". One tech guy thought the springs were aftermarket but another just reached in, felt them and said "no, these are stock" Evil John in particular knows his stuff. I went with a theme that penalized performance a bit because I knew the car was newer than they like to see. A 1st Gen gets through BS inspection easier. A TII will get you sweated but I don't think they do too well between fuel mileage and reliability.

If you go into your first race with the attitude of "what can I get away with?", you probably will run into problems one way or another. If you go into your first race paranoid, you will probably do well. Build for reliability first then worry about speed later. Read the rules, in particular the "how not to fail tech" in the Lemons rules for guidlines on how to build the car. You can build a human hamster ball to protect yourself but if it doesn't meet their guidlines you will fail tech. It's painful to watch guys bending up a new rollcage at the track because they didn't follow the rules. Unless you have your own tubing bender or lots of cash, I'd consider buying one of the pre-bent kits from someone like Roll Cage Components or S&W. Go with DOM over ERW as my guess that sometime in the future Lemons will only allow DOM. Buy a decent seat with lateral support, your body will thank you. The kirkey intermediate is reasonably priced. I've got a tube framed Sparco and it sucks. Apparently the comparable tube framed Corbeau sucks as well.

If you want to race and gets lots of track time, these series will get you the most time/dollar. Expect to spend $4k or so on your $500 car but you get to amortize that a bit each time you run it. Both series have websites with forums that have a classifieds section. Both have cars for sale in them and that will be a lot cheaper way to go than building your own. Don't drive like an a-hat and you will have fun and make lots of new friends. We're having a blast doing it.

jcocke 12-01-11 07:13 PM

So I've got an '86 FC that is a great candidate for Chump Car, though I admit, I am having trouble finding 10 "legit" $500 ads. I've got 5-7 real $500 car ads from craigslist...but that's about all I have found. What is the secret to finding these ads?

P.S. I'm looking for ads for the S4 (86-88) RX7s, since that is what I have.

mschiap 12-02-11 11:11 AM

No secret -just keep running searches on Craigslist. AutoTempest.com is a handy tool.
Check the Chumpcar rules, they are looking from ads from different geographic regions.

jcocke 12-02-11 06:51 PM

Yea I used searchtempest to find the ones I have...I guess I'll keep looking every month or so to see if there are any newer ads.

cagedruss 01-09-12 07:49 PM

5 Attachment(s)
Here is our Chump Car/ Rat Race / Roll-X car. We have lot of venues here now in the NW.

Sorry it is not a RX but I used what I have plenty of parts for. I do have two customers running first gens with good results.

Pictures of the engines are two mishaps we have had in the past two season. Our next race is mid March at Seattle in the inaugural Roll-X race.

cagedruss 01-11-12 11:38 AM

Here is the link to the Roll X race at Pacific Raceways for those interested.

LINK

CBear3 02-01-12 03:39 PM

Here's our Lemon. We've run the past two races at Autobahn. Lost a water pump with a few hours to go last time out. Not sure just how bad the engine is hosed, but I do know the compression is down to 60 psi in the front and 105 in the rear.

http://farm7.staticflickr.com/6227/6...0cb00c66c9.jpg

parid 04-15-12 01:22 PM

jcocke - Sorry I didn't see this sooner. I'm happy to share my AIV docs with you. That goes for anyone else as well. These are for an n/a S4.

parid 04-15-12 01:28 PM

This thread needs a lot more love. Here have some chumpcar wall love videos:

http://www.youtube.com/watch?v=wk12c4iCBuU

http://www.youtube.com/watch?v=3U6qWcEGazo

kenjinski 04-17-12 12:26 PM

nice!

555ideways 04-21-12 10:32 AM

Hey guys,
Been running an FC in lemons the last few years. Had a decent result at NJMP last week. Looking to see how far an NA FC can go on one tank of gas. How long are your fuel stints? Do you run it until it you hiccup? Is that bad for the rotary?

-Paddy

555ideways 04-21-12 10:34 AM

We also keep on burning through headers. We've been using the Racing Beat header and it just blows a hole through the 90 degree bend just off the exhaust port. Anyone else have problems like this? I've been trying to convince my guys to go back to the OEM header for reliability. It's a cast piece right? Should deal with the heat better than this aftermarket junk - no?

-Paddy

7dust 04-21-12 11:20 AM


Originally Posted by 555ideways (Post 11063452)
Hey guys,
Been running an FC in lemons the last few years. Had a decent result at NJMP last week. Looking to see how far an NA FC can go on one tank of gas. How long are your fuel stints? Do you run it until it you hiccup? Is that bad for the rotary?

-Paddy

We can run our turbo rotary a little over an hour and burn 15 gallons-ish out of the fuel cell. We have a 22 gallon cell but can only get about 15 before it hiccups because of slosh.

When our car was bridgeported, thats all we did was fuel. We burned 150 - 180 gallons per race. Ran badass, was super loud, emptied the stock tank in 45 minutes or less.

We are adding a surge tank for Eagles Canyon and hope to get more usable fuel out of the cell.

Its a TERRIBLE idea to hiccup a turbo rotary because a hiccup under boost is a receipe for detonation. We always come in at the first sign of fuel problems.

On an NA, the only thing problem is you might actually run out of gas an end up getting towed in. Been there.

parid 04-22-12 07:31 PM

Totally depends on the track and weather conditions. We have an S4 n/a. Laguna Seca, bright sunny day, nice cool air, open track with light traffic, we can only go 1hr 40min or so on the stock tank. Portland, typical rainy race, we can go well well past 2 hours. I would say that 2 hours is typically possible but just. We have never run it low enough to hiccup. These are endurance race series :).

We have the stock header, were considering venturing into modified ones. I have lost count of how many races without exhaust issue on the stock manifold. 7? 8? Years. We will probably make our own. Fancy branded race parts isn't very lemons/chump ;).

cheseroo 04-25-12 09:54 PM

Again, it depends on the track but we use about 10-15 gal every 1.5 hrs on our S5 NA.

rotarygod 05-15-12 09:08 AM

A few of my friends and I are looking into Chump Car and Lemons to see which one we'd prefer. I've been told Chump Car is for people who don't "get" Lemons. From what I've seen Lemons is more of an art car parade at higher speed or perhaps a side show circus act on a race track. I'm sure many find it fun but we kind of think it's a bit...well...stupid. We just want to race a cheap car for a long time. That's it. No bribes, no long division on a black board while wearing a wig, no margarita machines in the back seat, no bbq pits on the exhaust, no blow up dolls, hobby horses, etc. That would seem to point more towards Chump Car. We need to hang out at each race for a while. Maybe we'll change our minds since many people have said Lemons is a great time. We are still open to each being an option but at the moment we are favoring Chump Car. We don't want to be on the track with 150 other cars either. We are going to a Chump Car event this weekend. Maybe we'll find that it people are a bit too serious.

I've thought about the exhaust manifold issue. We have no desire to build a bridgeport turbo blending monster that overheats every 30 minutes. We'd probably run a more or less stock na motor. I was concerned about the heat issue with headers and my idea is one that I did early on when I first got into rotaries. The na cast exhaust manifold only has a 2" outlet. I once cut this off and welded on a sch. 40, 2-1/2", 45 degree weld el in it's place. When it's done it looks stock but the mod was only about $5 not counting labor. You've now got the flow of a 2-1/2" pipe rather than a 2" and it's still tough. Make sure you've got someone that really knows how to weld cast iron. A simple mid weld job isn't going to last.


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